Floating structures such as a dock, a jetty, a raft, etc. constructed from a single floating unit or a plurality of floating units assembled together, which can be utilized or towed, are well known.
For the floating structure constructed from a plurality of floating units assembled together, U.S. Pat. No. 8,037,837 B2 assigned to Candock Inc., Canada, discloses a dock unit attachable to another dock unit with a fastener for forming a floating dock. Likewise, for assembling a plurality of floating units as disclosed in European patent application, publication No. EP 2 682 336 A1 owned by Marine System Europa S.L., Spain, floating units are interlinked to each other in a jointed form by means of connectors being in the form of perforated projections and bolts.
In said existing inventions as described above, the floating unit has protrusions each of which is laterally extended for receiving the respective fasteners or bolts, thereby the floating unit can be attached to another floating unit. This structure has several disadvantages including: these components are easily damaged; and the components of the floating unit formed by a plastic molding may leads to a complicated mold, so that it may cause increases in production cost of the floating unit.
Meanwhile, in the invention according to European patent application, publication No. EP 0 385 903 A1 owned by S. A. Ateliers Polyvalents Chateauneuf, France, floating units are attached together by using bolts and nuts having four horizontal arms each of which is adapted in order to be fitted into a cavity on the lower surface of the floating unit, so that the floating units can be attached together without using any protrusions for receiving the bolts. However, since said floating units are attached together by screwing-in force for the bolts, it is possible that the bolts may be loosened.